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3g Upgrade Plug Question

  • Thread starter Thread starter Grabbin' Asphalt
  • Start date Start date Jul 30, 2013
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Grabbin' Asphalt

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Aug 4, 2013
#21
  • Aug 4, 2013
  • #21
I stated earlier that i had the yellow/ white connected like stock from "D" plug(way #2)
then i tried the yellow/white loop PA style (way #3)
so i've done both ways.
i will go back to the stock wiring and recheck loads.
did check that yellow/white stock wiring and it did get 12.65v at Atl plug, so fuse is good.
 
Last edited: Aug 4, 2013

Grabbin' Asphalt

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Aug 5, 2013
#22
  • Aug 5, 2013
  • #22
Ok here's the retest numbers with yellow/white back on the "D" plug along original stock wiring harness.

Engine off:
Battery + - = 12.65v
Alt stud = 12.65v

Engine at idle:
battery + - = 14.44v
Alt stud = 14.64v

Engine @ idle(750 rpm with e-cam) with lights and all accessories on high:
Battery : 13v
Alt stud : 13.33v

Engine @ 2000 rpm with lights and all accessories on high
Battery = 14.45v
Alt stud = 14.65v

Beginning to think this is just another issue other than an Alternator problem.
In neutral I control rev it slow, perfect sound, timing, idle etc
When I turn on the head lights or turn on the a/c controls while doing the slow control rev
it skips or hesitates around 3000-3500 rpms.
With radio playing it does not skip or hesitate either.
Fuel pressure doesn't change, no drop, spike etc during the skip or misfire.
Have a new billet MSD distributor 7months old, MSD coil 7 months old, spark plugs and wires are a couple months old, they still look fine,
no cracks in the boots. cap/rotor look good as well.
New fuel filter 1 day old, walbro 25ol pump 7 months old

Put a new stock coil on and the skip drops to 2000-2500 rpms with the lights and all on.
No codes, starts up fine, idles perfect.

Maybe a TPS problem, I'll get some readings when I can.
 
Last edited: Aug 5, 2013

jrichker

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#23
  • Aug 5, 2013
  • #23
Do you have a stock distributor and TFI that you could swap back in? MSD parts (May Suddenly Die) have been known to cause problems that are hard to find. They seem to get worse as the engine warms up.
 

mikestang63

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Aug 27, 2012
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Aug 5, 2013
#24
  • Aug 5, 2013
  • #24
jrichker said:
Do you have a stock distributor and TFI that you could swap back in? MSD parts (May Suddenly Die) have been known to cause problems that are hard to find. They seem to get worse as the engine warms up.
Click to expand...

View attachment 182367

AH......... now the truth comes out.... lol

MSD= CRAPOLA . I've run 11's with the stock distributor and TFI, coil. IMO there is no reason to upgrade unless you run a power added and I would not go MSD.
 

Grabbin' Asphalt

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#25
  • Aug 5, 2013
  • #25
Don't have either to test but I pulled my plugs and they look like toothpicks on the center electrode.
 
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